The invention relates to an electromagnetic switch relay and more particularly to such a relay having a visual indicator.
Switch relays are used in a variety of technical fields and particularly in the automotive industry. Switch relays exist in a variety of structural forms. For example, published patent application DE 19 920 742 A1 shows an electromagnetic relay having a base, a magnet system and an armature spring, in which the magnet system has an armature on which two lever sections are integrally formed. The lever sections form support points for the armature spring. A further support point for the armature spring is located on a fixed relay part. By bending the fixed relay part, the armature and thus a contact spacing may be adjusted.
One problem with known switch relays is that the switch state (closed or open) of the relay is frequently unascertainable. In the case of known relays, the contact arrangements may be checked through a viewing window in the relay housing. The contact spacing is constructed to be large enough so that when the switch contact is open, its state is visually recognizable. This construction has the disadvantage, however, that the contacts have to be arranged in the vicinity of a viewing window in the housing and moreover that the contact spacing when the contact is open must be made sufficiently large.
An object of the invention is therefore to provide an electromagnetic switch relay where the switching status is more readily recognizable.
Another object of the invention is to provide a display element for a switch relay for the purpose of displaying the switch position of the switch relay.
The switch relay according to the invention has a display element which is mounted movably, is in operative connection with the switch contact and is movable in dependence on the position of the switch contact from a rest position to a display position. The use of a mechanical display element provides the advantage that a clearly visible display of the switching status is possible regardless of the position of the contact elements. Furthermore, the display element provides the possibility of converting a small change in the contact spacings or a small change in the position of the armature into a clear alteration in the position of the display element, by way of the display element. This makes it possible to recognize the switching status of the switch relay simply on the basis of a clear alteration in the position of the display element.
Preferably, the display element is not connected directly to the switch contact, but is in operative connection with a component whereof the position is dependent on the position of the switch contact. In a preferred embodiment, the display element is in operative connection with the armature or an armature spring.
A flexible connection point having a pointer is included in the display element to enlarge the movement of the contact or armature. This makes a clearer display of the switch position possible. Preferably, the deflection of the switch contact is enlarged by way of a lever action and is converted to a larger deflection of the pointer or display element.